Typically calls from wireline telephony callers to Public Safety Answering Points (PSAP) (e.g. Enhanced 9-1-1 (E911) and United States Department of Transport Next Generation 9-1-1 (NG9-1-1)) and other similar answering points are routed to a correct answering point based on a location of the caller derived from the Dialed Number Identification Service (DNIS) (e.g. 9-1-1 in the case of emergency) and Automated Number Identification (ANI) of the caller. The answering point is provided with location information for the caller based on the physical location of the wireline service that the call originated from, based on the ANI number and associated address information. Cellular (a.k.a. mobile) telephony calls to an answering point are also typically routed based on DNIS/ANI, but methods to physically locate the caller based on geographic location through the use of GPS, triangulation and serving tower location are used in providing the answering point with location information for the caller.
With the advent of Voice over Internet Protocol (VoIP) and Voice over Instant Messaging (VoIM) calls (comprising a voice and/or an Instant Messaging (IM) component), a caller may not have an associated ANI and the physical location of the caller cannot be derived from any physical connection to the caller or by means of Wireline Registration, GPS, triangulation or cellular tower location. When a call from a cellular (a.k.a. mobile) terminal utilizes IP connectivity to originate a VoIP/VoIM call, or when the cellular terminal is a dual-mode appliance (e.g. WiFi/WiMax capable) and uses the non-cellular capability to originate a call, current cellular techniques to determine the location of the cellular terminal will not be triggered and/or are not able to determine the correct location.
Given that the answering point to which a call is routed is selected as a function of the location of the caller, a growing proportion of PSAP and other answering point calls (e.g. VoIP and VoIM calls) fail to be routed correctly utilizing current known processes and systems because the caller's location can not be reliably determined.
What is needed is an apparatus and method for IP-based call answering point selection and routing.